Pressure is rising and going above 3 bar. I set the pressue at 1.2 bar and after a while running on c/h the pressure rises to above 3 bar, any ideas?
too much water in system and not enough air in expansion vessel . depressurise and pump air into expansion vessel at top of vessel , with a bicycle pump.
Either the filling link is letting by or the expansion vessel has gone. you can try to recharge the expansion vessel with a foot pump if that fails new filling link or expansion vessel
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